1. Field of the Invention
The present invention relates to a UPS (uninterruptible power supply) system and, more particularly, to a mobile rack type battery box for use in a UPS system.
2. Description of the Related Art
A conventional UPS (uninterruptible power supply) system, either of a small scale for computer or the like or a big scale for industrial machine or server, as shown in FIG. 1, comprises a housing 1 defining a storage chamber 11, and a plurality of battery cells 2 mounted in the storage chamber 11 and electrically connected in series. When city power supply failed, the UPS system immediately provides the necessary working voltage to the apparatus at the load, keeping normal running of the apparatus. This UPS system battery arrangement design has numerous drawbacks as outlined hereinafter.
1. When power low, the battery cells 2 must be detached from one another and disconnected from the power circuit in the UPS system.
2. Because the battery cells 2 are directly installed in the storage chamber 11 inside the housing 1 of the UPS system and not properly shield with EMI (electromagnetic interference) protective shielding means, the radiation of the storage battery 2 may interfere with normal functioning of surrounding electronic components or apparatus.
3. Because the battery cells 2 are directly installed in the storage chamber 11 inside the housing 1 of the UPS system and not properly shield, there is a risk of short circuit.
4. Because the battery cells 2 are installed in the storage chamber 11 in vertical, the height of the UPS system cannot be minimized to fit a small electric apparatus.
The present invention has been accomplished to provide a mobile rack type battery box for a UPS system, which eliminates the aforesaid drawbacks. It is therefore the main object of the present invention to provide a mobile rack type battery box, which is portable and can conveniently be installed in a UPS system. It is another object of the present invention to provide a mobile rack type battery box, which is simple and inexpensive to manufacture. It is still another object of the present invention to provide a mobile rack type battery box, which provides good ventilation. It is still another object of the present invention to provide a mobile rack type battery box, which shields the radiation of the battery cells, preventing interference with surrounding electronic devices. It is still another object of the present invention to provide a mobile rack type battery box, which keeps the electric wires of the battery cells well arranged, eliminating the risk of short circuit. It is still another object of the present invention to provide a mobile rack type battery box, which occupies less vertical installation space. It is still another object of the present invention to provide a mobile rack type battery box, which has means to hold the loaded battery cells in position. It is still another object of the present invention to provide a mobile rack type battery box, which is automatically electrically connected to the UPS system when inserted into the storage chamber of the UPS system. It is still another object of the present invention to provide a mobile rack type battery box, which has coupling means on the outside such that a number of mobile rack type battery boxes can be coupled to one another and arranged in a stack. According to one aspect of the present invention, the mobile rack type battery box comprises two symmetrical cover shells fastened together and defining a holding space, the cover shells each having a horizontal base wall, a vertical front wall, a vertical back wall, a vertical left sidewall, and a vertical right sidewall, said horizontal base wall having at least one longitudinal inside groove for receiving electric wires; and a plurality of battery cells mounted in the holding space inside the cover shells and horizontally abutted against one another. According to another aspect of the present invention, the cover shells each have an opening in the respective vertical back wall. The opening of the vertical back wall of one of the cover shells is mounted with a power output socket for output of battery power from the battery cells. The opening of the vertical back wall of the other of the cover shells is blocked with a sealing plate. According to still another aspect of the present invention, the vertical left and right sidewalls of the cover shells each have a plurality of beveled ribs disposed at an inner side and adapted for friction engagement with the battery cells to hold the battery cells inside the cover shells. According to still another aspect of the present invention, the cover shells each have longitudinal ribs and longitudinal grooves alternatively disposed in the respective horizontal base wall on the outside such that a number of mobile rack type battery boxes can be coupled to one another and arranged in a stack by engaging the longitudinal ribs of one cover shell of one mobile rack type battery box into the longitudinal grooves of one cover shell of another mobile rack type battery box.